Spherical receiver tank and method of making same



April 5, 1938. R. A. SANDBERG 2,113,060,

SPHERICAL RECEiIVER TANK AND METHOD 0F MAKING S'AME Filed Sept. 2, 1957 lfiff i 16 /6 30 3 I 57 if, /3 2/ la @6 T 34 Mb RAY A. SANDBERG x I @II 3 1 /4- Patented Apr. 5, 1938 UNITED STATES PATENT OFFICE SPHERICAL AND METHD Q i Q OF MAKING SAME Bay A. Sandberg, Waukegan, 111., assignor to Oakes Products Corporation, North mm, 111., a corporation ofMichig Application September 9 Claims.

This invention relates to stamped metal spherical containers and includes the process of making the containers.

More specifically the invention relates to spherical receiver tanks-for mechanical refrigeration systems.

Mechanical refrigeration systems of the compressor-condenser-evaporator type usually have incorporated therein, between the condenser and the evaporator, a tank or closed receptacle for storing condensed refrigerant; The refrigerant is fed from the receiver tank to the evaporator unit. 1 Since the refrigerant in the receiver tank is usually under pressure it is highly desirable that these receiver tanks bemade sufficiently strong to withstand high internal pressure. same time, however, it is desirable to form the receiver tanks from as thin gauge metal as possible in order to decrease the weight of the unit and also decrease the manufacturing cost.

According to this invention, a spherical or ballshaped tank is formed from a very thin gauge metal and is so assembled as to be able to with-,

stand high internal pressure. It is known that a spherical tank will withstand higher internal pressures without bursting than a tank of any other shape since the pressure is uniformly distributed in a spherical receptacle.

According to this invention, the tank is formed i from hemispherical stamped metal male and female cups. The rim of the female cup member is provided with an outturned annular flange. The open mouth of the male cup member is then readily inserted into the female member since thefiange on the female member facilitates a seating of the male member in the female member. v

A support is provided for the spherical tank composed of a stamped metal disc formed with a concave cup-receiving portion.

Circular openings are formed in'the top and bottom of the tank for receiving bosses or fittings therein. The suppo member for the tank receives the bottom fitting therethrough and reinforces the tank around the opening through the bottom thereof. The bottom fitting connects with the supply line to the evaporator unit in' a refrigerator system.

The metal surrounding the opening in the top of the tank is-reinforced by a washer member disposed on the inside of the tank around the top fitting thereof. The top fitting receives -a purge valve for blowing entrapped air and other gases from the refrigerant in the tank.

At the z, 1931, Serial N' 162,092 (on. 1 13-l20) A refrigerant inlet tube or fitting extends from the tank near the top thereof.

The entire assembly is brazed together by a. single brazing operation.

It is thenan object of this invention to provide strong spherical-tanks formed from sheet metal.

Another object of this invention is to provide spherical receiver tanks for refrigerator systems.

A further object of this invention is to reinforce metal surrounding openings for fittings and the like in thin gauge metal receiver tanks.

A further object of this invention is to provide a. method of making spherical tanks wherein all of the constituent parts of the tanks. are integrally united by a single brazlngoperation.

A further object of this invention is to provide spherical tanks for refrigerator systems having fittings integrally secured thereto and extending through openings provided in the tanks together with reinforcing means for strengthening the tank metal around the openings receiving the fittings. I

Other and further objects of this invention will become apparent to those skilled in the art from the following detail description of the annexed tank having special fittings secured thereto, it should be understood that the tanks of this invention are adapted to wide usage and that different types of fittings can be used without departing from the scope of the invention. "On the drawing;

1 is a side elevational view of a receiver tank according to this invention. Figure 2 Is am enlarged vertical cross-sectional view taken through a receiver tank assembly, with parts shown in elevation, illustrating the manner in which the parts of the tank are assembled prior to the brazing operation.

Figure 3 is an enlarged detail view shown in vertical cross-section illustrating the manner in which the male and female cup members form-' ing the tank are assembled for the brazing operation. Figure 4 is an enlarged fragmentary vertical cross-sectional view illustrating the manner in which the fittings for the tank are assembled in the male cup member, prior to. the brazing operation.

Figure 5 is an enlarged vertical cross-sectional fragmentary view, with a part in'elevation, illusscribed in connection with a refrigerant receiver plug" member for closing the bore.

trating the manner in which 'the support for the In Figure 1 the reference numeral Ill designates generally a receiver tank according to this.

invention. The tank comprises a hemispherical metal male cup member Ii having the open end thereof seated in a. hemispherical female metal cup member l2. The female cup member l2 has an outturned flange l3 formedaroun'd the rim thereof for a purpose to be hereinafter more fully described.

The female member l2 has a support l4 for the tank l0 secured to the bottom portion thereof and a fitting l5 extending through the support I4 and through the bottom of the cup member l2.

The male cup member I I has secured thereto a top fitting l5 extending through the top thereof and a tube or fitting 26 extending therethrough in spaced relation from the top thereof.

According to this invention the various con stituent parts of the receiver tank III are assembled so as to be integrally united by a single brazing operation. For this purpose an assembly such as is shown in Figures 2 to 5 is made prior to the brazing operation.

The cup members II and I2 are formed by stamping or drawing thin gauge sheet metal of a type suitable for brazing. Brass sheets, copper plated steel sheets and the like metals are preferred.

As best shown in Figures 2 and 4, a circular opening I! is punched through the top of the male cup member II.

During the stamping operation a flat portion 18 is formed around the opening H.

The fitting has a cylindrical shank portion- Ilia extending from the bottom thereof. A shoulder lGb is formed between the shank portion Ilia and the main head portion of the fitting I 6.

The shank We of the fitting I6 is inserted through the opening I! of the metal cup member ll until the shoulder lib of the fitting rests snugly on top of the flat portion l8 surrounding the hole l1.

The fitting I5 has a bore extending therethrough (not shown) and may receive therein a The fitting l6 serves as a means for'purging the interior of the tank from entrapped air and gases.

A wire I!) of a brazing "metal such as brass or any other metal capable of alloying with the fltting l6 and the metal cup II is disposed around the shank portion Ilia of the fitting IS.

A washer 20, somewhat U-shaped in crosssection, is slipped over the shank i6 a of the fitting with the leg 2| thereof snugly disposed around the shank I611. The other leg 22 of the washer abuts the inner surface of the male cup member H and is shaped to have an area contact with the cup member. The washer has a large radius defining a cavity 23 in which the wire I9 is located. The washer 20 can be staked into position as by means of a prick punch so that it will be held'tightly against the metal cup member II at the time the assembly is brazed. The washer serves to reinforce the metal surrounding the opening I! in the male member and makes possible the use of very light gauge metal for the male member without danger of blowing out the The male member Ii is also punched to form an opening therethrough-in spaced relation from the opening II. In forming the opening 24 the cup member II is preferably pierced from the inside so as to extrude an annular flange 25 around the opening 24.

The tubular fitting 26 is inserted into the opening 24 in contacting relation with the flange 25. The tube 26 serves as a fitting for introducing refrigerant from the condenser of a refrigerator system into the tank. A brazing wire 2'! is disposed around 26 on top of the flange 25.

The bottom of the female clip member [2 is pierced from the outside to form a circular opening 28 therein defined by an inturned flange 29. The flange 29 is formed during the piercing operation.

A cylindrical shank portion l5a of the fitting I5 is inserted through the opening 28 and snugly engages the inner wall of the flange 29. A shoulder l5b is formed between the head of the fltting l5 and the shank of the fitting I5a. This shoulder l5b abuts the cup member l2.

A brazing wire 30 is disposed around the fitting iiiadjacent theshoulder I517.

The support member I4 is then disposed around the fitting i 5 and seated against the .cup member l2.

' The support I 4 can be formed by stamping a circular metal disc to provide a raised portion the tube l4a thereon having a concave face M1) for receiving female cup member l2. The central portion of the concave base I4b is pierced to provide a circular opening 3| therethrough defined by a downturned annular flange 32.

Slots or holes 33 are'punched through the flat portion of the support member l4 near the outer periphery thereof so that the support can be bolted or screwed to the base plate of a refrigerator apparatus.

The support member I4 is slipped over the'fltting member l5 with the flange 32 thereof snugly engaging the fitting i5. This provides a ch am-- ber 34 in which the brazing wire 30 is disposed. As pointed out above, the rim of the female member l2 has an outturned flange i 3 formed thereon preferably at right angles to the mouth of the member I2. I

The male member ll then has the-open end thereof seated into the mouth of the female member l2 as shown at H a in Figures 2 and 3.

The flange l3 forms a support .for a brazing wire 35.

The entire assembly as shown in Figure 2 is then placed in a brazing furnace and heated to brazing temperature. i

If brass brazing wires are used the assembl is heated to temperatures around 1800" F. Obviously other temperatures for different types of brazing wires can be used without departing from the scope of the invention.

The brazing wires I1, 21, 30, and 35, when the assembly is heated to the brazing tempera tures, alloy with the fittings and the cup members to integrally unite the adjacent surfaces.

of these members and thus form an integral unit. If the brazing wires are heated above their melting points the brazing metal will flow by capillary action between the contiguous surfaces of the cup members and fittings to form, upon solidifying, a solid solution or alloy 35 as shown fitting when the interior of the tank is under A pressure.

5 preciated that the accompanying illustrations are somewhat diagrammatic in so far as they illustrate the brazing wire and the fiow oi the same under heat. It is understood, however,

that the brazing wire should be so positioned in close proximity to the outer extremities of the surfaces to be' brazed as to enable thedesired flow of the brazing wire.

If desired, as when making the larger size receiver tanks, a second brazing wire 81 (Figure 2) can be disposed in the space-between the female cup member i2 and the upturned portion I la. of the support member ll. Usually, how ever, the brazing wire 30, as shown in Figure 2, is suflicient to unite the support I! with the female cup member l2 and also to integrally braze the fitting I! with the cup member.

The flange l3 on the male cup member I! serves a three-fold purpose of facilitating the insertion of the portion Ha of the male member ll into the mouth of the female member II, .of forming a support for the brazing wire 35, and of rigidifying and strengthening the final assembly against distortion.

The washer 20 serves a dual function of providing a seat for the brazing wire l8 and of re? inforcing the metal of the cup member ll surrounding the opening H for the fitting l6.

Likewise the support It serves a three-fold function of providing a support for the tank,

hi defining a cavity for the brazing wire 30 and of reinforcing the metal of the cup I! around the opening 28 for the fitting lb.

The provision of reinforcing members around the large openings in the tanks of this invention has made it possible to use very light gauge metal for forming the tanks. For example, the cup members II and I! have been made of metal around .037 inch in thickness and the tank assembly will withstand hydrostatic internal pressures between 1,000 to 1,200 lbs. per square inch. When the reinforcing members, such as a washer 20 was not used, the area of the cup member ll around the fitting I5 is distorted and even torn loose at much lower pressures with such light gauge stock metal.

I am aware that many changes may be made "'and"numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I,

therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

1. The method of making a spherical container G0 which comprises providing male and female hemispherical metal cup members, forming an outturned flange on the rim of the female cup member, piercing a relatively large hole through 'the base 'of the female cup member to form an (:5 inturned annular flange around the hole, providing a support member having a concave seat portion for receiving the bottom of the female cup member, piercing a hole through the center of the support member, inserting a fitting through 7 the hole of said support member and into the hole at. the base of the cup member, disposing a brazing wire around the fitting between the support and the cup member, inserting the open mouth of the male member into the female member, disposing a brazing wire on the flange of ror alloying the brazing metal with the parts to integrally unite the same. a

2. In the method of making metal containers having fittings integrally united therewith, the

steps which comprise providing ,a segmental spherical metal cup member, forming a hole hole, disposing a brazing metal around the cylindrical shank portion in the cup member, seating a washer having an outturned flange around the cylindrical shank portion of the fitting with the flange of the washer contacting the cup member,

said brazing metal being between'the cup member and washer, and' heating the assembly to through the cup member, inserting a fitting having a cylindrical shank portion through said members, inserting fittings having cylindrical shank portions in said holes, disposing a stamped metal support-member having a concave face around the fitting on the flanged cup member, interposing a brazing wire between the support member and the cup member, said support member receiving the cup member on the concave face thereof, said fitting in the hole of the other cup member having a cylindrical shank portion extending into said cup member, disposing a flanged washer aroundthe cylindrical shank portion of said fitting in saidcup member, said washer having a flange adapted to contact an area of said cup member surrounding said hole, interposing a brazing wire between the washer and the cup member, seating the open end of said cup member in the flanged cup member, disposing a brazing wire on the flange adjacent the seated cup member and heating the assembly to brazing temperature for alloying all of the brazing wires with the adjoining parts to integrally unite the parts.

4. A container comprising integrally united male and female cup members, said female cup member having an outturnedflange thereon to rigidify the structure, inlet and outlet secured to said cup members and a support surrounding one of said fittings and united to said female cup member.

5. A spherical receiver tank comprising male and female hollow hemispherical cup members, said female cup member having an outturned flange formed around the rim thereof and said male member having the open end thereof seated in said female member and integrally united therewith, a fitting extending into the male cup member and having a cylindrical shank portion therein, a flanged washer disposed around said shank portion in said male cup member and having a fiange integrally united with the metal of the cup member surrounding the opening in which the fitting is seated, a fitting extending' through thebottom of the female cup member having a shank portion extending from the cup member, an annular metal base portion disposed around said shank of the fitting and having a concave face integrally united with the female cup member.

lapping margins thereof,

6. A spherical receiver tank for refrigerator assemblies comprising opposed hollow hemispherical cup members in interfitting relation and integrally joined together along the over- I fittings extending through the top and bottom of said cup members and reinforcing metal members including flanges snugly surrounding the fittings and other flanges extending outwardly from the fittings, said flanges being respectively united to the fittings and cup members to reinforce the metal of the cup members surrounding the fittings.

'Z. A light gauge metal spherical refrigerant receiver tank comprising opposed top and bottom metal hemispherical cups, said bottom cup having an outturned flange around the mouth thereof and said top cup having the open end thereof seated in the mouth of the bottom cup and brazed thereto to form a closed spherical tank, said tank having circular openings in the top and bottom thereof, metal fittings secured to said tank and having cylindrical shank portions extending through said openings, a metal washer in the tank brazed around the top fitting and having a face thereof brazed to the inner face of the top cup around the opening therein, and a metal disc on thebottom of the tank brazed around the bottom fitting and having a concave face brazed to the outer face ofthe bottom cup around the opening therein.

8. A spherical pressure retaining tank comprising stamped metal hemispherical male and female cups, and an integral outturned pennanentflange around the mouth of the female cup only, the mouth of said male cup being inserted into the mouth of the female cup and extending therein in telescoped relation thereto, the inserted portion of the male cup being integrally brazed to the female cup and said flange on the female cup remaining as a permanent rigidifying means for the tank;

9. A pressure retaining vessel comprising opposed hollow male and female cup members, an integral outtumed flange around the mouth of the female cup member only, the mouth of the male member being inserted in the mouth of the female cup member and extending therein in spaced relation from. the flange thereof, a fitting extending through one of said cup members, a support for said vessel surrounding said fitting, the inserted por ion of the male cup member being integrally brazed to the female cup member, the fitting and support surrounding the fitting being integrally'brazed together and to the adjacent cup member and said flange on the female cup member rigidifying the vessel.

. RAY A. SANDBERG. 

